Method of and means for varying the circumference of printing cylinders



Jan. 5, 1954 H. w. HUFFMAN 2,664,821 METHOD OF AND MEANS FOR VARYING THE CIRCUMF'ERENCE OF PRINTING CYLINDERS Filed March 13, 1951 lo I2 FIG. 3 I6 I 62 so 64 INVENTOR.

HAROLD w. HUFFMAN BY WW ATTORNEY Patented Jan. 5, 1954 METHOD OF AND MEANS FOR VARYING THE CIRCUMFERENCE OF PRINTING CYLINDERS Harold W. Huffman, Hamilton, Ohio, assignor to The Hamilton Tool Company, Hamilton, Ohio,

a corporation of Ohio Application March 13, 1951, Serial No. 215,352

8 Claims.

This invention relates to rotary printing cylinders, and more particularly to a printing cylinder having an adjustable circumference.

An object of the present invention is to provide an adjustable circumference printing cylinder which is characterized by an elfective printing area which is substantially co-extensive with the circumferential area of the cylinder.

Another object of the invention is to provide an adjustable circumference printing cylinder which comprises a base or carrier cylinder to which various interchangeable sets of complementary half cylinder shells may be selectively secured.

Still a further object of the invention is to provide an adjustable circumference printing cylinder having the hereinabove described characteristics wherein the cylinder shells which comprise a set are constructed and arranged for relative limited movement about the axis of rotation of the carrier cylinder to which they are mounted.

A further object of the invention is to provide a plurality of interchangeable sets of half-cylinder shells having complementary front and rear ends, wherein the rear ends are provided with intermeshing members for facilitating relative movement of the cylinder shells about a common axis while precluding relativeendwise movement thereon, and wherein the front ends of the shells comprising each set are provided with means for drawing them together for tensioning a printingplate carrier-sheet onto and around the outer surface of the shells comprising a set for securing the shells together and for providing a mini mum gap or space between the opposite ends of the printing-plate carrier-sheet. This feature is of prime importance in those instances wherein it is desirable or essential to reduce to an absolute minimum the non-printed portion between the adjacent ends of consecutive sheets printed by the printing cylinder.

Still a further object of the invention is to provide an adjustable circumference printing cylinder assembly comprising a plurality of interchangeable sets of half cylinder shells of different diameters and a plurality of printing-plate carrier-sheets dimensioned to be wrapped once around the outer circumference of the shells comprising a set, wherein the opposite ends of the carrier sheets are secured to and carried by the front end edges of the complementary half cylinder shells, and wherein the carrier sheets are utilized to hold the respective half cylinder shells which collectively comprise a set onto the carrier cylinder.

Another object of the invention is to teach a method of simply though effectively varying the circumference of a printing cylinder.

Still another object of the invention is to provide a composite, adjustable circumference, printing cylinder having the hereinabove described characteristics wherein the width of the printing-plate carrier-sheet is less than the overall length of the various half cylinder shells comprising a given set for providing an area adjacent the opposite edges of the shells through which shell-clamping means may extend for securely though releasably mounting the shells to a carrier cylinder.

Another object of the invention is to provide a plurality of interchangeable sets of cylinder shells, each set having outer arcuate printingplate carrier-sheet supporting surfaces, said shells being fabricated from a light-weight material, thereby enabling an operator to easily handle the shells for mounting them onto or removing them from the carrier cylinder of a rotary press.

These and other objects are attained by the means described herein and as disclosed in the accompanying drawings in which:

Fig. 1 is a. side plan view of an adjustable circumference printing cylinder embodying the teachings of the present invention.

Fig. 2 is a sectional view taken on line 2-2 of Fig. 1.

Fig. 3 is a view similar to Fig. 2 but wherein the half cylinder shells comprising a set have been illustrated in a fully opened position.

With reference now to the drawings, the numeral I0 denotes generally a base or carrier cylinder of a rotary printing press, wherein the diameter of cylindrical portion ii] is of a dimension less than the minimum printing-cylinder-circumference to be utilized.

A plurality of interchangeable sets of half cylinder shells is adapted to be securely though re leasably mounted onto the carrier cylinder for providing a composite printing cylinder having an effective circumference determined by the particular job being run. The present invention is particularly adapted to provide interchangeable sets of cylinder shells which are constructed and arranged to provide a minimum gap or spacing between the opposite ends of a printing plate carried by the composite printing cylinder.

The numerals i2 and I l denote generally a pair of complementary half cylinder shells which collectively comprise a set, each shell including an arcuate outer surface it concentric with the axis of rotation of the carrier cylinder, said outer sur- 3 face determining the effective circumference of the composite printing cylinder.

Each of the shells includes complementary, substantially straight, continuous, forward end edges l8, and a pair of complementary rear edges provided throughout their length with interrneshing or interlocking means in the form of alternate tongue and groove portions 20 and 22, see Fig. 1, wherein the tongues 28 of one shell are arranged to be received within and slidably engage the grooves 22 of the other shell for facilitating limited relative rotation of shells l2 and is about a common axis, while effectively precluding relative endwise axial movement between said shells.

In the preferred embodiment of the invention each of forward end edges 58 is provided with an elongated downwardly inclined slot 2 3 extending th full length of each shell.

As best illustrated in Fig. 3, the front end edges it are constructed and arranged whereby to be laterally spaced during those periods of time when the tongue and grooves of the respective shells have been shifted to a fully nested position. Suitable fastening means, such as, by way of example, a bolt 38, may spanningly engage the front end edges ii! of the shell halves comprising a set for drawing these edges toward one another for effecting relative movement of the respective shells about carrier cylinder is resulting in partial separation of the tongue and groove portions to the position illustrated in Fig. 2.

The numeral denotes generally a. flexible carrier sheet the length of which is suflicient to enable it to be wrapped once around the outer arcuate surface of shells l2 and i4 and for disposing opposite ends of the sheet in slots 2%.

A printing plate 32 is secured to and carried by th carrier-sheet, being affixed thereto by means of a suitable adhesive.

As best illustrated in Fig. 1, the width of the carrier sheet is of a dimension less than the overall length of shells l2 and i i which collectively comprise a set for thereby providing an annular band having a width denoted generally by the letter T in which bolt 35 is located for thereby enabling the half shells to be drawn together for tensioning the carrier-sheet therearound for effectively and securely binding the shell segments together and for anchoring them onto the carrier cylinder. The flexibl carrier-sheet d may be fabricated from steel, zinc, sheet plastic, or other suitable material.

In the preferred embodiment of the invention and for increasing the safety characteristics of the composite printing cylinder, suitabl auxiliary fastening means such as bolts 65 and 19 may be provided for securely though releasably anchoring those portions of shells I2 and Hi, respectively, remote from their forward edges directly to the carrier cylinder, however it should be understood that the auxiliary fastening means 68 and is may be omitted, especially when using cylinder shells of comparatively small outside diameters.

Fastening element BE! may comprise a bolt, the head of which is received within a suitable aperture E2 provided in the outer face of the carrier cylinder for thereby enabling the bolt head to be counter-sunk below the outer surface of the cylinder. The shank of the bolt may be received within threaded bore 64 tapped radially into the carrier cylinder. It will be noted that fastening element 63 will enable the operator to securely though releasably anchor shell cylinder I2 relative to and upon the outer circumference of the carrier cylinder. e

The head of fastening element H3 is receivable within elongated countersunk slot 12 which is in open communication with a shank-receptive elongated slot M for thereby facilitating relative motion of shell is about the axis of the carrier cylinder. A threaded bore 76 is radially disposed in cylinder ill, as illustrated.

Fastening means to will be loosely disposed within bore 16 until after fastening means 3; has been manipulated for tensioning the carrier sheet onto the outer surface of shells l2 and M, as best illustrated in Fig. 2, after which fastening means l'fl may be tightened for thereby precluding accidental or unintentional relative shifting of shells i2 and I l.

With particular reference now .to Fig. 2, it will be noted that the adjacent edges 80 of printing plate d2 are almost in contacting relationship whereby the gap or space therebetween is reduced to a minimum. In this connection it will be noted that the spacing illustrated in 2 is considerably wider than would occur in actual practice, such illustration being solely for the purpose of indicating some lateral separation between edges It should be understood, of course, that if desired edges as could be designed whereby to be in contacting relationship rather than laterally spaced, as illustrated.

It Will be understood that the shell" may be fabricated from any suitable light-weight material such as, by way of example, cast aluminum, and in those instances wherein the effective outer circumference of the shell sets is as illustrated in the drawings, or larger, they may be provided with a plurality of laterally spaced, inwardly projecting radial members 53 having arcuate bearing portions 92 dimensioned to closely and accurately follow the contour of the outer cylinw'cal surface of the carrier cylinder. The spacing between the laterally spaced radial members r be undercut as at a l, thereby effectively re the overall weight of the shells without impairing their efficiency.

What is claimed is:

1. An adjustable circumference printing cylinder comprising, in combination, a carrier cylinder, a pair of complementary half-cylinder shells each including forward and rear edges wherein the rear edges are provided throughout their length with alternate tongues and grooves, the tongues of one shell slidably engaging the grooves of the other shell for permitting limit-ed rotary motion while precluding relative ar'al movement between said shells, radial members projecting inwardly from each shell adapted to abuttinqly engage portions of the outer surface of the carrier roll for providing an effective circumference in excess of and spaced parallelism with the outer surface of the carrier roll, and clamping means including a flexible printing-plate carrier-sheet circumscribing said shells and means spanningly interconnecting said shells for movement on the carrier cylinder for tensioning said sheet onto and around said shells while iultaneously clamping them onto the carrier cy l 2. An adjustable circumference printing cylinder comprising, in combination, a carrier V der, a pair of complementary half-cylinder shells each including forward and rear edges wherein the rear edges are provided throughout their length with alternate tongues and grooves, the tongues of one shell slidably engaging the grooves of the other shell for permitting limited rotary motion while precluding relative axial movement between said shells, radial members projecting inwardly from each shell adapted to abuttingly engage portions of the outer surface of the carrier roll for providing an effective circumference in excess of and in spaced parallelism with the outer surface of the carrier roll, a flexible carrier sheet circumscribingly engaging said shells, means securing opposite ends of said sheet to a forward edge of each shell, and means interconnecting the shells adjacent their forward edges for tensioning said carrier sheet around the shells for clamping them directly onto and in driven relationship with the carrier cylinders.

3. A composite, adjustable circumference, printing cylinder comprising a carrier cylinder, a pair of complementary cylinder shell segments having forward and rear edges and outer arcuate surfaces concentric with the axis of the carrier cylinder, a flexible prinlng-plate carrier-sheet wrapped once around the pair of shell segments, the width of said sheet being of a dimension less than the overall length of the shell segments, means spanningly interconnecting the forward edges of the shell segments beyond the side edges of the carrier-sheet for imparting relative rotary movement to said shell segments for tensioning a carrier-sheet onto the shell segments for securing them together in driven relationship with the carrier cylinder, and other means extending ra dially through said shell segments and into said carrier cylinder for securely though releasably anchoring the shell segments in advanced carrier-sheet tensioning position directly to the carrier cylinder.

4. An adjustable circumference printing cylinder comprising, in combination, a carrier cylinder, a pair of complementary half-cylinder shells each including substantially straight, continuous forward edges and rear edges provided throughout their length with interlocking means for permitting limited rotary, nesting motion while precluding relative axial movement between said shells, radial members projecting inwardly from each shell adapted to abuttingly engage portions of the outer surface of the carrier roll for providing an effective circumference in excess of and in spaced parallelism with the outer surface of the carrier roll, a flexible printing-plate carriersheet dimensioned to circumscribe said shells with its free ends secured one to each shell adjacent its forward edge, means extending radially through one of said shells into the carrier cylinder for fixedly securing one of said shells directly onto the carrier cylinder, clamping means secured to and carried by the forward portions of the shells for drawing the forward edges of the second shell toward corresponding forward edges of the first shell for tensioning the carrier-sheet around said shells and for simultaneously clamping them onto the carrier cylinder, and other means extending radially through the second shell into the carrier cylinder for fixedly securing the second shell in advanced position directly to the carrier cylinder.

5. A composite, adjustable circumference printing cylinder comprising a carrier cylinder, a pair of cylinder shell segments, a flexible printing-plate carrier-sheet positioned around said segments, means for securing an opposite end of said sheet to each of said shell segments, and means secured to, carried by and spanning the shell segments for rotating said segments on the carrier cylinder toward one another for tensioning the carrier sheet therearound and for simultaneously clamping the said shell segments onto and in driven relationship with the carrier cylinder.

6. A composite printing cylinder comprising a carrier cylinder, a pair of complementary cylinder shell segments receivable on said carrier cylinder, each shell segment including a forward and a rear edge, a flexible printing-plate carriersheet disposed around the shell segments with its opposite ends secured to and carried by the opposed adjacent forward edges of the shell segments, and means secured to and carried by said shell segments for moving them relative to the carrier cylinder for drawing their aforesaid forward edges toward each other for tensioning the carrier-sheet on and around said shell segments while simultaneously clamping the shell segments onto and in driven relationship with the carrier cylinder.

7. A composite printing cylinder as disclosed and described in claim 6, wherein the rear edge of the cylinder shell segments are provided with complementary interlocking members for permitting relative rotary motion between the shell segments while precluding relative endwise axial movement therebetween.

8. The method of varying the effective circumference of a printing cylinder which comprises the steps of providing a carrier cylinder having a circumference less than the minimum desired printing circumference, of mounting a pair of half cylinder shells onto the carrier cylinder for increasing its circumference to the desired circumference, of wrapping a flexible printing-plate carrier-sheet around the shells, and of then slidably shifting said shells on and circumferentially relative to said carrier cylinder by pulling the forward edge of one of said shells toward the adjacent edge of the other of said shells for tensioning the carrier sheet thereon and for thereby clamping the cylinder shells onto the carrier cylinder.

HAROLD W. HUFFMAN,

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,763,124 Barber June 10, 1930 2,135,150 Schmidt Nov. 1, 1938 2,285,116 Grupe June 2, 1942 2,454,170 I-Iiester Nov. 16, 1948 

